Geometric changes allow normal ejection fraction despite depressed myocardial shortening in hypertensive left ventricular hypertrophy

Objectives.This study of hypertensive left ventricular hypertrophy 1) assessed myocardial shortening in both the circumferential and long-axis planes, and 2) investigated the relation between geometry and systolic function.Background.In hypertensive left ventricular hypertrophy, whole-heart studies have suggested normal systolic function on the basis of ejection fraction-systolic stress relations. By contrast, isolated muscle data show that contractility is depressed. It occurred to us that this discrepancy could be related to geometric factors (relative wall thickness).Methods.We studied 43 patients with hypertensive left ventricular hypertrophy and normal ejection fraction (mean ± SD 69 ± 13%) and 50 clinically normal subjects. By echocardiography, percent myocardial shortening was measured in two orthogonal planes; circumferential shortening was measured at the endocardium and at the midwall, and long-axis shortening was derived from mitral annular motion (apical four-chamber view). Circumferential shortening was related to end-systolic circumferential stress and long-axis shortening to meridional stress.Results.Endocardial circumferential shortening was higher than normal (42 ± 10% vs. 37 ± 5%, p < 0.01) and midwall circumferential shortening lower than normal in the left ventricular hypertrophy group (18 ± 3% vs. 21 ± 3%, p < 0.01). Differences between endocardial and midwall circumferential shortening are directly related to differences in relative wall thickness. Long-axis shortening was also depressed in the left ventricular hypertrophy group (18 ± 6% in the left ventricular hypertrophy group, 21 ± 5% in control subjects, p < 0.05). Midwall circumferential shortening and end-systolic circumferential stress relations in the normal group showed the expected inverse relation; those for ∼33% of the left ventricular hypertrophy group were >2 SD of normal relations, indicating depressed myocardial function. There was no significant relation between long-axis shortening and meridional stress, indicating that factors other than afterload influence shortening in this plane.Conclusions.High relative wall thickness allows preserved ejection fraction and normal circumferential shortening at the endocardium despite depressed myocardial shortening in two orthogonal planes

ACC/AHA 2006 Guidelines for the Management of Patients With Valvular Heart Disease. A Report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 1998 Guidelines for the Management of Patients With Valvular Heart Disease)

"The ACC and the AHA have long been involved in the joint development of practice guidelines designed to assist healthcare providers in the management of selected cardiovascular disorders or the selection of certain cardiovascular procedures. The determination of the disorders or procedures to develop guidelines for is based on several factors, including importance to healthcare providers and whether there are sufficient data from which to derive accepted guidelines. One important category of cardiac disorders that affect a large number of patients who require diagnostic procedures and decisions regarding long-term management is valvular heart disease. During the past 2 decades, major advances have occurred in diagnostic techniques, the understanding of natural history, and interventional cardiology and surgical procedures for patients with valvular heart disease. These advances have resulted in enhanced diagnosis, more scientific selection of patients for surgery or catheter-based intervention versus medical management, and increased survival of patients with these disorders. The information base from which to make clinical management decisions has greatly expanded in recent years, yet in many situations, management issues remain controversial or uncertain. Unlike many other forms of cardiovascular disease, there is a scarcity of large-scale multicenter trials addressing the diagnosis and treatment of patients with valvular disease from which to derive definitive conclusions, and the information available in the literature represents primarily the experiences reported by single institutions in relatively small numbers of patients.

Management of pregnant women with prosthetic heart valves

William H. Gaasch, Robyn A. Nort